A. Field of the Invention
The invention lies in the field of suspension of non-gaseous solid materials, these materials being in colloidal size and obtained by grinding very finely divided substantially pure magnesium metal in dry substantially easily burning low volatility petroleum, and in particular kerosene and also is in the field of suspensions of this colloidal dispersion of substantially pure magnesium (500 to 1 millimicrons) in jet fuel in critical proportions for the purpose of aiding combustion, there being no non-oxyhydrocarbons or non-hydrocarbon additives required for the addition and suspension and thereby controlling emissions, while improving fuel economy and efficiency.
B. Description of the Prior Art
1. Motor Fuel Economy and Emission Controls
The problem of fuel economy and emission controls has come to the forefront since the Arab Oil Embargo in 1973-74 and has gripped the attention of the public, the supplier of the add-on catalytic converter and the domestic oil industry in the United States. Interim efforts at emissions control due to automobiles are being directed to add-on pollution control devices, such as the platinum catalyst charged converter which cuts emissions to meet standards in the states and of the Federal Government. The results these past 10 years have been encouraging as stated by Gladwin Hill in the New York Times, Business Section, page A15, who reports as follows:
In 1966, when cars began using exhaust controls, the Los Angeles County Air Pollution Control District reported that the area's 3,770,000 cars were spewing out 10,485 tons of carbon monoxide each day, 1,805 tons of hydrocarbons (unburned gasoline) and 545 tons of oxides of nitrogen.
Today, with 4,470,000 cars in the area, the total is down to 5,040 tons of carbon monoxide, a 50 per cent decrease, 625 tons of hydrocarbons, a two-thirds decline, and 530 tons of oxides of nitrogen. Nitrogen oxide controls are relatively new and difficult to remove.
In 1966, there were 271 days of excessive oxidants (compounds formed from car fumes by sunlight, and often irritating to the eye); 89 days of excessive nitrogen oxides, which accounts for the brownish tint to smog, and 365 days of excessive carbon monoxide.
In 1973, there were 185 days of excessive oxidants, 59 days of excessive nitrogen oxide, and 116 days of excessive carbon monoxide.
For the first 10 months of 1974, the totals were 202 days of excessive oxidants, 44 days of excessive nitrogen oxides and 71 days of excessive carbon monoxide.
A significant part of the problem in pollution is the problem of air craft using jet fuels and the risks are comparable to those of the auto emissions except on a smaller scale.
2. Prior Art Patents
a. Methods of Preparing Colloidal Metal Suspensions
Various methods are known for making colloidal metals, for example, Vaughn, U.S. Pat. No. 2,123,617, describes a method of making colloidal metal by reaction in liquid ammonia, and the literature makes references to electrolytic processes for the manufacture of colloidal magnesium.
These prior methods are expensive to carry out, because of the high cost for equipment and the need for highly skilled personnel, not to mention the high energy requirement for electrolytic processing. A further important disadvantage is the formation of impurities, oxides or nitrides, which occurs because of the high reactivity of magnesium.
In contrast to the above methods for preparing colloidal magnesium, the present process carries out the grinding by starting from 400 mesh pure (99.8+%) magnesium powder, which is dispersed in dry kerosene. The dispersing liquid is substantially free from water, and thus eliminates one of the most important reactions of metallic magnesium, which is that with water. Under ordinary atmospheric conditions or in pure water or saltfree water of high pH, however, the reaction is self-stopping, because of the formation of an insoluble hydroxide film: EQU Mg + 2 H.sub.2 O .fwdarw. Mg(OH).sub.2 + H.sub.2
b. Finely Divided Magnesium in Fuels
The patent to Toulmin, Jr., U.S. Pat. No. 3,122,429, discloses a slurry of magnesium finely divided coal and ozone in jet fuel in weight ratio of 25/75 solid fuel to liquid fuel.
The patent to Toulmin, Jr., U.S. Pat. No. 3,147,091, discloses a composite fuel of 35% by weight of powdered coal and magnesium and remainder liquid hydrocarbon.
The patent to Nixon et al, U.S. Pat. No. 3,709,747, discloses 50 to 70% by weight of finely divided metal in JP-4 Jet fuel with emulsifier and formamide.
The patent to Nixon et al, U.S. Pat. No. 3,732,084, discloses 60% by weight of finely divided coal and emulsifier in JP-4 Jet fuel and formamide.
A common concept in the pumpable fuel formulations of the Nixon et al and Toulmin, Jr. patents is the requirement for one or more emulsifier additives or polar organic liquid additives such as metal soap catalysts in Toulmin Jr. or formamide-urea as dispersing agent to serve to coat the particles of finely divided solids, such as metals or coal dust.
A further common concept in the Nixon et al and Toulmin, Jr. patents is the calorific requirement of the powdered solid, such as metal in order to increase the thrust of the jet fuel. For example, the preferred quantity of finely divided carbon in Nixon et al is from 20 to 68 weight percent of the liquid fuel and obvious this substantial amount provides a major calorific contribution to thrust. In Toulmin, Jr. special mention is made of the need for combustible coal and metal to produce high fuel temperature and maximum B.T.U. values under conditions where ignition temperatures range from 200.degree. up to 1,000.degree. C and more (see U.S. Pat. No. 3,122,429, column 6, lines 70 to 72 and lines 30 to 32).
In contradistinction to these prior art patents, the present fuel uses substantially no calorific amount of powdered metal and is restricted to low ignition temperatures relying on critical proportions and autocatalytic action, which uniquely coacts in improving combustion without overheating.